The background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
Distributed Raman amplifiers provide for greater transmission distances through pumping optic fiber transmission lines. However, the power of the pumping laser can exceed the physical capability of the transmission line to support the pumping activity, thereby damaging the fiber or optical components. In order to prevent such damage, a distributed Raman amplifier sends a short duration probe pulse down the transmission line to detect by return signals if there are optical losses. If the optical losses are too severe, the distributed Raman amplifiers will shut down. If the optical losses are less severe or low, the distributed Raman amplifier will begin pumping the transmission line.
In some scenarios, multiple optical point-loss sources are proximate to a distributed Raman amplifier where the aggregated sources individually contribute to optical losses that are so significant that the distributed Raman amplifier shuts down. For example, multiple optical connectors disposed within a carrier hotel could contribute to aggregated optical losses that would cause the distributed Raman amplifier to fail to pump the transmission lines.
Interestingly, a major supplier of optical network infrastructure suggests, in such scenarios, an “alternative solution would be to ‘homerun’ fibers, which means bypassing some patch panels.” Such an approach is not practical in carrier hotels and is not a cost effective solution.
U.S. patent application publication 2007/0030558 to Martinelli et al., titled, “Raman-Amplified Optical Transmission System and Method for Amplifying Optical Signals”, filed Jun. 13, 2006, describes a scenario where a lumped Raman amplifier is coupled with a distributed Raman amplifier. The lumped Raman amplifier, disposed behind the distributed Raman amplifier, achieves localized gain, possibly via a spooled high-Raman efficiency amplification fiber. Although the Martinelli approach provides for additional gain via a spooled fiber, the Martinelli configuration would still fail in the carrier hotel environment as the aggregated losses would still cause the distributed Raman amplifier to shut down.
Thus there remains a signification need to offset optical losses in environment where optical point-loss sources are proximate to a distributed Raman amplifier.
All publications identified herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
The following description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, reaction conditions, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term “about.” Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
Unless the context dictates the contrary, all ranges set forth herein should be interpreted as being inclusive of their endpoints and open-ended ranges should be interpreted to include only commercially practical values. Similarly, all lists of values should be considered as inclusive of intermediate values unless the context indicates the contrary.
As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all Markush groups used in the appended claims.